The dependence of the intensity of Raman bands of pyridine at a silver electrode on the wavelength of excitation

Discovered by Wood in 1902, grating anomalies have fascinated specialists of optics for more than one century. Long after the first interpretation given by Rayleigh, Fano has suggested that the origin of anomalies could be found in the excitation of surface waves. This chapter describes the quantitative phenomenological theory of Wood’s anomalies developed in the 1970s, based on the interpretation given by Fano and on the macroscopic laws of electromagnetics. This theory leads to a formula giving the efficiency of gratings in the region of anomaly and predicts the phenomenon of total absorption of light by a grating.

https://www.springer.com/cda/content/document/cda_downloaddocument/9783642280788-c2.pdf?SGWID=0-0-45-1336210-p174287160

Theory of Wood’s Anomalies

We demonstrate here a surface impedance imaging technique based on sensitive dependence of surface plasmon resonance (SPR) on local surface charge density. By applying a potential modulation to a sensor surface, we are able to simultaneously obtain three images: the dc component and the amplitude and phase of the ac component. The dc image measures local molecular binding activity on the surface, as found in the conventional SPR imaging technique, and the ac images are directly related to the local impedance of the surface. Our experimental data can be analyzed quantitatively in terms of the simple free electron gas model for the sensor surface and the Randles equivalent circuit model for interfacial impedance.

Surface impedance imaging technique.

Surface plasmon resonance microscopy (SPRM) is a versatile platform for chemical and biological sensing and imaging. Great progress in exploring its applications, ranging from single-molecule sensing to single-cell imaging, has been made. In this Minireview, we introduce the principles and instrumentation of SPRM. We also summarize the broad and exciting applications of SPRM to the analysis of single entities. Finally, we discuss the challenges and limitations associated with SPRM and potential solutions.

Surface Plasmon Resonance Microscopy: From Single-Molecule Sensing to Single-Cell Imaging.

We show that roughened surfaces of hyperbolic metamaterials scatter light preferentially inside the media, resulting in a very low reflectance. This phenomenon of fundamental importance, demonstrated experimentally in arrays of silver nanowires grown in alumina membranes, is consistent with a broad-band singularity in the density of photonic states. It paves the road to a variety of applications ranging from the stealth technology to high-efficiency solar cells and photodetectors.

/pdf/reduced-reflection-from-roughened-hyperbolic-metamaterial-3qg6gx9ek2.pdf

R Orlowski

Papers

The total reflection of light at smooth and rough silver films and surface plasmons